Are shiv bhagwan are the second of aadinath bhagwan
No. In Jainism, Adinath (Rishabhanatha) is the first Tirthankar. The second Tirthankar is Ajitnath (Ajitanatha). Shiv (Shiva) is not recognized as a Tirthankar in Jain scriptures.
- Adinath is the first Tirthankar.
- Ajitnath is the second Tirthankar.
- There is no tradition in Jainism that identifies Shiv as the second Tirthankar; Shiv is a Hindu deity and outside the Jain Tirthankar lineage.
Both Digambar and Shwetambar traditions agree on Ajitnath as the second Tirthankar. You can read more here